Twelve years ago, in early August, an obscure political group called Swift Boat Veterans for Truth rolled out an ad in three hotly contested battleground states. It featured several veterans who served in John Kerry’s unit in the Vietnam War alleging that the Massachusetts senator had falsified his war record, a central pillar of the heroic life story he had been telling for months on the presidential campaign trail. The media put the ad’s claims in the spotlight for much of the slow news month of August, and even though they were widely denounced, Kerry became damaged goods only a month after accepting the Democratic nomination.

Meanwhile, the candidate who benefited from the “swiftboating,” President George W. Bush, suffered no real blowback from ads that smeared a decorated war veteran on his behalf. Voters—other than angry Kerry supporters—didn’t hold Bush responsible for the sketchy commercial that did so much to ensure his reelection.

This year, in her coming face-off with Donald Trump, Hillary Clinton needs to do what George W. Bush did back then: Find a way to take the opponent down, hard, but without voters connecting her to the attacks. Bush was unpopular in 2004, and couldn’t risk muddying himself any more. Clinton is now even less in favor with the American public: She has the second-lowest favorability ratings of any (presumptive) presidential nominee in the history of polling. Fortunately, Trump ranks Number One on that list. But even so, Clinton needs to steer clear of looking like a mudslinger.

That explains why Clinton’s anointed super PAC, Priorities USA, will be the one hammering Donald Trump throughout the summer and fall, rather than Clinton’s own campaign. The covert assault began this week, when Priorities unleashed its first two televised attack ads hammering Trump in the battleground states of Ohio, Virginia, Florida, and Nevada. They show Trump swearing, promising to defund Planned Parenthood, assessing a woman’s “fat ass,” and talking about blood “coming out” of Megyn Kelly:

Brace yourself for months more of such ads: Priorities is sure to continue using Trump’s own words against him, in various and damning combinations. And why wouldn’t they? He makes it so easy, and it’s all right there, on Twitter and on tape, ready to be spliced into something that sounds even more revolting than the original.

Relying on Priorities USA could also give Clinton a leg up on Trump this spring and summer. For now, at least, Trump doesn’t have one main super PAC to counter her attack-by-proxy strategy. As Politico has reported, a messy and fascinating power struggle has been raging between at least 24 super PACs that say they are supporting the presumptive Republican nominee. Two of the most active—Great America PAC and Committed for American Sovereignty—are jockeying to become the main surrogate for the Trump campaign in the general election. Others, according to Politico, “appear to be spending most of their money on contracts with favored consultants,” rather than funneling it into efforts to boost the candidate. As a result, Trump advisors have disavowed several groups, and now, the rival PACs are accusing each other of being scams.

Campaign-finance laws bar Trump from coordinating with a super PAC. But until he can make it clear, indirectly, that one main group has his blessing, this power struggle will continue. Big donors won’t know where to go, and as a result, Trump won’t be able to raise the big money—at least $1 billion, according to experts—needed to keep up with Clinton.

We won’t know until November, of course, whether Priorities’ attacks will put a lasting dent in Trump. But the likelihood is they’ll do him some damage—without any collateral damage to Clinton’s favorability. That’s because the idea of outsourcing attacks is based on more than the Swift Boat precedent: There’s growing evidence that negative ads really do work better when they come from an outside group. New research shows that the ads bankrolled by those outside groups with the vague, patriotic names are an almost foolproof way to bludgeon any opponent without generating any blowback for the candidate. In fact, having allies launch super PAC attacks can actually make a candidate like Bush—or Clinton—look better in voters’ eyes.


Candidates and their operatives have long known that going negative can be risky. “When a candidate airs a negative ad against their opponent, voters tend to form a more unfavorable opinion of the attacker,” says political scientist Pat Meirick, who studies political advertising at the University of Oklahoma. That’s why campaigns have tended to delegate their dirty work to outside groups—a trend that was accelerated by the 2010 Citizens United decision that allowed wealthy individuals and corporations to spend to their hearts’ content. But until recently, the research about attack ads sponsored by PACs was ambivalent. Did they really persuade voters? Did they carry any of the same risks of backfiring on a candidate?

In 2015, political science professors Conor Dowling and Amber Wichowsky laid those questions to rest when they published a paper in the American Journal of Political Science. They found that PAC ads insulate candidates from almost all the backlash that comes with negative campaign ads. As expected, voters in their experiment viewed candidates who did their own attacking less favorably than before they saw the ads. But here’s what was unexpected: Voters viewed that same candidate more favorably after watching a super PAC ad assaulting her or his opposition. This is what Dowling and Wichowsky call an “attack without consequence.”

There’s another reason why super PAC attacks work better: Studies show that voters trust these shady outside groups more than they trust politicians. “Citizens tend to see these groups, like Americans for Prosperity or Priorities USA, as more credible than your typical politician who you are predisposed to distrust,” says Erika Franklin Fowler, who directs the Wesleyan Media Project, tracking campaign ads in presidential elections.

And for reasons having everything to do with her gender, Clinton might be more vulnerable than Trump to having attack ads boomerang on her and make her look worse. “There is a gender component to these attacks,” Fowler says. “Female candidates run the risk of sounding shrill and having other adjectives used against them. Having an outside voice to play that surrogate role is always helpful to candidate, but particularly helpful to a woman.”

Meanwhile, Trump has his own problems—namely, having do his own dirty work until he has a super PAC ready to help demolish Clinton. Not that he minds too much, one suspects; it’s hard to remember a presidential candidate who’s had a better track record of ruthlessly, gleefully demolishing his foes. But now that he’s facing a general-election audience, he can’t afford to drive his favorability ratings lower as he tries to do the same to Clinton. Which makes it possible that—as difficult as it may be to believe—we may be about to enter a stretch of the 2016 campaign in which Donald Trump is out-attacked.